How starch type affects blood sugar, metabolism and gut health in people with insulin resistance
Impact of Starch Digestibility on Glycemic Variability and Control, Cardiometabolic and Inflammatory Profiles, Microbiota and Intestinal Health in Subjects With Insulin Resistance
This 2-month diet test will try whether eating more slowly digestible and resistant starch reduces blood sugar swings and improves metabolism, inflammation, and gut bacteria in adults with insulin resistance.
Quick facts
| Phase | Not applicable |
|---|---|
| Study type | Interventional |
| Enrollment | 40 (estimated) |
| Ages | 18 Years to 75 Years |
| Sex | All |
| Sponsor | Mondelēz International, Inc. Industry-sponsored |
| Drugs / interventions | chemotherapy |
| Locations | 1 site (Lyon) |
| Trial ID | NCT07408479 on ClinicalTrials.gov |
What this trial studies
Forty adults with insulin resistance will follow a balanced diet either high or low in slowly digestible starch (SDS) and resistant starch (RS) for two months while researchers regularly collect blood, urine, and stool samples and use continuous glucose monitoring. Key outcomes include changes in glycemic variability, HOMA-IR (insulin resistance), lipid markers, inflammatory markers, and the composition and function of the gut microbiota. The intervention focuses on dietary replacement with starch products rich in SDS and RS and careful monitoring of dietary intake and body weight. Data will be used to link starch digestibility to metabolic and intestinal health measures.
Who should consider this trial
Good fit: Adults aged 18–75 with insulin resistance (HOMA-IR ≥ 2.5), BMI 25–40 kg/m², stable weight, waist circumference >80 cm (women) or >94 cm (men), low baseline fiber intake (≤25 g/day), willing to change diet for two months, able to read French and store stool samples at home are ideal candidates.
Not a fit: People without insulin resistance, with food allergies or intolerances to study products, BMI or activity levels outside the entry ranges, or who cannot comply with diet changes or sample storage are unlikely to benefit from this protocol.
Why it matters
Potential benefit: If successful, this could offer a practical dietary approach to reduce blood sugar variability and improve metabolic and gut health in people with insulin resistance.
How similar studies have performed: Smaller clinical and dietary studies of resistant starch and slowly digestible carbohydrates have shown modest improvements in postprandial glucose and shifts in gut microbiota, but findings are mixed and larger targeted studies in insulin-resistant adults remain limited.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria: • General criteria: * Age between 18 and 75 years (bounds included) * HOMA-IR ≥ 2.5 * Body Mass Index (BMI) between 25 and 40 kg/m² (bounds included) * Stable weight over the past 3 months (+/- 5% of body weight) * Waist circumference \> 80 cm for women, \> 94 cm for men * Sedentary subject or subject practising regular and stable physical activity for the duration of the study (maximum 4 hours per week) * Able to understand the provided information and having signed the informed consent forms * Able to read and write in French * Having a freezer and comfortable with storing stool samples at home * Having undergone a prior medical examination during the screening visit Food-related criteria: * Willing to modify their diet for 2 months * No food intolerances or allergies * Regular consumption of the study products * Fiber intake ≤ 25 g/day * Willing to consume three main meals with no more than one snack per day and to take meals or snacks at least two hours apart Exclusion Criteria: * General criteria: * Adult under legal protection (guardianship or curatorship) * Person with unstable medical or psychological conditions that, according to the investigator, could lead to non-compliance or non-cooperation during the study or compromise safety or participation (as per Articles L.1121-6, L.1121-8, L.1121-9, and L.1122-1-2 of the French Public Health Code) * Presence of a condition identified during clinical examination or medical interview that could interfere with study evaluations, as judged by the investigator * Person deprived of liberty by judicial or administrative decision * Failure to comply with the exclusion period of another study as indicated in the "national volunteer database" * Person exceeding the annual compensation limit for participation in research protocols * Tobacco (or vaping equivalent) consumption \> 5 cigarettes per day and inability to abstain from smoking or vaping from the evening prior to exploration days specified in the protocol * Alcoholism or alcohol abuse (\> 30 g/day). Consuming more than three alcoholic drinks per day is considered abusive. One alcoholic drink corresponds to 30 mL of spirits, 120 mL of wine, or 330 mL of beer or abuse or dependency on another drug * Person not affiliated with a social security system or benefiting from a similar scheme * Absence of valid, approved health certificates in the event of government measures during an exceptional epidemic situation * Biological criteria: * Fasting blood glucose ≥ 7 mmol/L or ≥ 1.26 g/L * Triglycerides \> 4 g/L * LDL-cholesterol \> 1.90 g/L * eGRF (estimated glomerular filtration rate) \< 60 ml/min * Other biological abnormality with significant clinical relevance according to the investigator * Population-related criteria : * Person with a specific dietary regimen (vegetarian, lacto-vegetarian, vegan, high-protein, low-carbohydrates, weight-loss diet, etc.) * Person consuming dietary supplements (prebiotics, probiotics, or minerals such as divalent cations like magnesium and calcium) regularly in the month before the selection visit and during the study * Blood donation within 2 months prior to the selection visit * Claustrophobia preventing indirect calorimetry measurement * Limited venous access making blood sampling and catheter placement difficult * Therapeutic and medical criteria: * Type 1 or Type 2 diabetes * Systolic blood pressure ≥ 140 mmHg * Diastolic blood pressure ≥ 90 mmHg * Hypertension treatment * Known endocrine pathology interfering with carbohydrate metabolism (uncontrolled thyroid dysfunction, acromegaly, hypercortisolism, etc.) * Gastrointestinal diseases with an inflammatory component or associated with malabsorption or considered likely to interfere with the results of the study; * History of bloody diarrhea * Exocrine pancreatic insufficiency * History of bariatric surgery * History of digestive surgery, except appendectomy and simple hernia repair * Severe eating disorders (e.g., anorexia, bulimia, binge-eating disorder, night-eating syndrome) as judged by the investigator; * Hepatocellular insufficiency * Immunosuppressed individuals (e.g., those with AIDS, lymphoma, long-term corticosteroid therapy, chemotherapy, or allogeneic transplant) * Central venous catheter carriers and post-surgical patients * Any other clinically significant unstable or untreated abnormality in the immunological, neoplastic, endocrine, hematological, gastrointestinal, hepatic, neurological, or psychiatric domains, as judged by the investigator * Obesity medication use within the past 3 months or during the study * Antibiotic use in the month prior to explorations (for common beta-lactam antibiotics) or within 3 months before explorations (for other antibiotics), as judged by the investigator * Daily laxative use within the 3 months prior to explorations or other medications significantly interfering with gut microbiota composition; * Use of treatments that could interfere with study measurements, as judged by the study's co-investigating physicians * Pregnant, planning to become pregnant (verified by a blood pregnancy test), or breastfeeding woman * Person with known allergy to adhesive materials
Where this trial is running
Lyon
- Centre de Recherche en Nutrition Humaine Rhone-Alpes — Lyon, France (Recruiting)
Study contacts
- Principal investigator: Anne-Laure Castell, MD — Centre de Recherche en Nutrition Humaine Rhone-Alpe
- Study coordinator: Julie-Anne Nazare, PhD
- Email: julie-anne.nazare@univ-lyon1.fr
- Phone: +33 4 78 86 29 81
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.